1. Field of the Invention
The present invention relates to a method of cladding an outer tube with an inner tube by detonating explosive charges.
2. Description of the Prior Art
It is known to expand a corrosion-resistant inner tube into contact with an outer, mechanically strong tube by means of an explosion process, so as to obtain a mechanical pressure joint between the two tubes. It is also known to bind the two tubes metallurgically over the whole of their contacting surfaces by means of an explosion-welding process.
In the case of the mechanical pressure joint, one drawback is that in the case of large diameters and thin cladding tubes, there is a risk that the latter tube will become inwardly distorted should a vacuum be generated in the conduit.
In the case of the metallurgical joint, the risk of inwardly distorsion does not exist, since a joint of this nature has a high mechanical strength, even against radially and inwardly acting stresses.
An explosion-welding process, however, is expensive, particularly in the case of large diameters, which require very large quantities of explosives and supportive fixtures. In practice, explosion-welding processes are restricted to tube lengths of 4-5 metres.
These drawbacks are avoided with the inventive method, both with solely mechanical joints and also with explosion welds effected over the entire surface of the tubes.